Wire lifting crane



Jan. 5, R McLAlN r WIRE LIFTING CRANE 2 Sheets-Sheet l Filed Jan. 22,1949 RAY 0 Am THEODORE A. FBRNKAHL I INVENTOR.

ATTORNEY 1954 R. M LAIN ETAL 2,665,012

WIRE LIFTING CRANE Filed Jan. 22, 1949 2 Sheets-Sheet 2 Rmr Mc Lam.

INVEN TOR.

BYW%W ATTbRNEY THEODORE H. FORNKAHL Patented Jan. 5, 1954 OFFICE WIRELIFTING CRANE Ray McLain and Theodore A. Fornkahl, Cape Girardeau, Mo.

Application January 22, 1949, Serial No. 72,122

This invention relates to a wire lifting crane for use on powerdistribution poles. More specifically it relates to a crane of the kinddescribed having a boom which is pivoted for motion in a vertical plane.

An object of the invention is to provide a crane which can be mountedeither at the top of a pole or on a cross-arm.

Another object of the invention is to provide a crane having a boompivoted for limited pivotal motion in a vertical plane.

Still another object of the invention is to provide a crane having aboom which is rotatable about a vertical axis so that it can be utilizedwith either of two sets of positioning notches.

Yet another object is to provide a crane which is simple yet rugged.

A further object is to provide a crane which can be tilted from aposition in which the wire being lifted will clear the pole to one inwhich the wire lifted will be positioned over the insulator to which itis to be fastened.

Yet a further object of the invention is to provide suitable means forsupporting the crane on a pole.

These and other objects will become apparent from a study of thisspecification and the drawings which are attached hereto and made a parthereof and in which:

Figure l is a side elevation of the crane mounted on a cross-arm.

Figure 2 is an end elevation of the apparatus of Figure I viewed fromthe left thereof.

Figure 3 is a view partly in section showing the lower portion of theboom.

Figure 4 is a side elevation of the crane mounted at the top of a pole.

Figure 5 is an end elevation of the crane showing a modified form ofcross arm mounting means.

Referring now to Figures 1 to 3, the numeral I refers to a cross-armhaving an insulator 3 mounted thereon.

The crane comprises a channel shaped base 5 which is open downwardly andis proportioned so as to fit the top edge of a cross-arm. A pair ofhooks i extend laterally from the top of the base to support the chains9 and II which are connected by a toggle clamp mechanism I3 ofconventional construction.

Fixed to the upper face of the base are a pair of parellel, spacedsector plates I5 which are spanned by a back plate I'I. Each sector hasspaced notches l9 and 2|. The corresponding notches in the plates arealigned.

1 Claim. (Cl. 212-8) A pivot pin 25 is fixed in thesectors and a bearingor support member 27 is pivoted on the pin. The member has two guideportions 29, 3| which are separated by a groove 33.

The boom is preferably a tube formed with a downwardly curved upper end3'1 which terminates in an eye 39 which receives a pulley block 4| Thelower end of the tube is notched at 43 to receive the pin 25 andslidably receives the guide portions 29, 3|. A pair of pins 45 are fixedin the tube and extend radially into the groove 33. When the notches 53rest on the pin 25, the pins 55 rest at the bottom of the groove. Thispermits the boom to be lifted far enough to disengage the notches andpin.

A rope or other line 4? is supported in the block and a hook 43 may befastened to one end thereof to lift the power wire 5|.

Another pin 53 is fixed in the boom above the pins 45 and extends fromeach side of the tube. The pin is positioned so that it is seated in thenotches I9 when the lower notches 43 engage pin 25.

Operation The crane is mounted with the base 5 spanning the upper sideof the cross-arm and suitable links of the chains 9 and II are engagedwith, hooks I and with the toggle clamp I3. When the clamp is closed,the chain is tightened so as to hold the base firmly on the arm.

With the boom in the position shown in Figure 1, the hook 49 is loweredto the ground and engaged with a wire. The wire is then lifted until itis slightly higher than the insulator 3. The boom of the crane is thenswung toward the dotted line position (Figure 1 until the Wire isdirectly over the insulator upon which it is then lowered.

The pin 53 engages the ends of the notches I9 to limit the pivotalmovement of the boom.

When it is desired to use the crane to mount a wire on an insulator 55which is supported on top of a pole 51, the base is clamped to the sideof the pole by means of chains 9, II and toggle clamp I3. Thereafter theboom is slid outwardly on the support guides, away from pin 25. Thisdisconnects notches 43 from pin 25 and pin 53 from notches I9.

The boom (Figure 4) is then rotated degrees on guides 29, 3| and rotatedabout pin 25 until pin 53 is adjacent notches 2|. The boom is then slidtoward pin 25 to reengage it with notches 43 and pin 53 with notches 2|.

3 Operation of the device in this position is similar to that previouslydescribed.

Modified clamp (Figure 5) Instead of using the chain to clamp the craneon a cross-arm I may turn up the lower edges of the base to formchannels 59. A U-shaped clamp 6| has hooks 63 formed at the ends thereofto enter and interlock with the channels.

A threaded hub 65 is fixed to the center portion of the clamp and a handscrew 61 is mounted therein.

The application of the clamp is obvious.

It is obvious that various changes may be made in the form, structureand arrangement of parts without departing from the spirit of theinvention. Accordingly, applicant does not desire to be limited to thespecific embodiment disclosed herein primarily for purposes ofillustration; but instead, he desires protection falling fairly withinthe scope of the appended claim.

What I consider to be new and desire to protect by Letters Patent of theUnited States is:

In a crane, the combination of a base, clamping means for detachablymounting said base on a supporting means, a support member havingaxially aligned and axially spaced cylindrical guide portions, a tubularboom having a longitudinal axis, said boom having one end mounted onsaid guide portions for rotation and for axial translation thereon toand from a normal position, means on said boom extending into the spacebetween said guide portions for engaging them to limit the axialtranslation of the boom, apivot pin engaging said base and supportmember and cooperating therewith to mount said boom for movement throughan arc in a plane which intersects said base, means definingdiametrically opposed, axially directed notches in the end of the boom,said notches and pivot pin being engaged when said boom occupies itsnormal axial position and serving to hold the boom in one or the otherof two rotated positions, the other end of said boom being offset fromsaid axis, a pulley, means for mounting said pulley on said other end ofthe boom, stop engaging means mounted on said boom, said stop engagingmeans being moved in a predetermined path as said boom moves through itsarc while occupying said normal axial position and being moved out ofsaid path when said boom is displaced from said normal axial position,and a series of stop means mounted on said base and disposed at spacedpoints along the path of and for engagement with said stop engagingmeans, said stop means and stop engaging means serving to limit thepivotal motion of said boom to any selected one of a number of segmentsof its pivotal arc.

RAY MCLAIN. THEODORE A. FORNKAHL.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 272,745 Mumm Feb. 20, 1883 436,717 Moore Sept. 16, 1890475,923 Bowring May 31, 1892 481,408 Manley Aug. 23, 1892 490,632Ransome Jan. 24, 1893 647,777 White Apr. 17, 1900 663,109 Tucker Dec. 4,1900 841,404 Jay Jan. 15, 1907 971,686 Michael et a1. Oct. 4, 19101,021,545 Messick Mar. 26, 1912 1,070,022 Ehlich Aug. 12, 1913 1,190,141Friesner July 4, 1916 1,247,706 Moran Nov. 27, 1917 1,337,400 GarsonApr. 20, 1920 2,107,500 Price et a1. Feb. 8, 1933 2,390,192 St. ClairDec. 4, 1945

